Kyle Sandilands, who has lost his role on Australian Idol, as well as his radio show on a Sydney station Photograph: Sergio Dionisio/Getty

A controversial radio "shock jock" has been dumped as a judge on Australian Idol after a public backlash over a lie-detector stunt in which a teenage girl revealed she had been raped.

The Australian prime minister, Kevin Rudd, joined in with criticism of Kyle Sandilands's show, The Kyle and Jackie O Show, on the Sydney radio station 2Day FM.

Sandilands' lie detector stunt caused an outcry after the girl was strapped to a polygraph machine and quizzed by her mother about whether she was sexually active.

2Day FM has since taken The Kyle and Jackie O Show off air and Sandilands has been sacked from his role as a judge on the hit Network Ten reality talent show Australian Idol.

The mother volunteered to quiz her daughter, now aged 14, despite apparently already knowing she had been assaulted.

"I've already told you the story about this, and don't look at me and smile because it's not funny," said the girl. "Oh OK, I got raped when I was 12 years old."

Sandilands, who presented the show with Jackie O'Neil, was accused of further insensitivity when he asked: "Right, and is that the only sexual experience you've had?"

O'Neil then stepped in to end the interview and she and Sandilands apologised on air, saying they did not know the girl had been raped.

2Day FM said the show had been put "into recess" pending a review of the incident and the way it interacts with its audience. In a statement the station added that Sandilands was "unable to perform his on-air duties at this time".

The New South Wales state government has ordered police and child welfare officers to investigate the girl's rape claim, made in a segment on the radio show last Wednesday.

The Australian prime minister said: "This is really off. It's wrong, [it] shouldn''t be done. This is a young girl and I am, as I think most Australians are, really distressed at the way in which the young person has been treated in this way."

Sandilands has previously gained notoriety for stunts in which he drank breast milk and launched a competition to find Sydney's smallest penis. He said he was "disappointed" at the decision to drop him from Australian Idol.

Network Ten said it had become "increasingly clear that as [Australian] Idol has remained a family-focused show, his radio has taken on a more controversial position over this period which is not in the interest of the show".

Australian Idol is due to return for its seventh series on Sunday. It is understood Sandilands will appear in the first three episodes of the new series, which have already been filmed.

The broadcaster added in a statement: "The recent controversy surrounding Kyle's radio programme has highlighted more than ever the conflicting attitude of the two careers."

Family groups praised the decision to drop the DJ from the show. Bill Muehlenberg, spokesman for the Family Council of Victoria, told the Herald Sun newspaper: "Maybe he'll sit down and think about what a clown he's been and how he needs to lift his game."

In a statement, Jenny Parkes, Sydney general manager of 2Day FM's parent company Austereo, said: "Kyle Sandilands's management has advised Austereo that he is unable to perform his duties on-air at this time.

"Further, following a great deal of consideration and having consulted Jackie O and all stakeholders, Austereo has formed the view that it is in the interest of all parties, for the Kyle & Jackie O Show to go into recess until we have completed an across-the-networks review of the principals and protocols of our interaction with our audience.

"This review commenced last Wednesday 29 July 2009. Austereo will not make any further comment until the review is completed."

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